instance creatiion as an "event"

Steven Taschuk staschuk at telusplanet.net
Fri Apr 11 23:20:12 EDT 2003


Quoth Simon Burton:
> On Fri, 11 Apr 2003 17:15:32 -0400, Arthur wrote:
  [...]
> > The only thing I seem to be missing is some kind of "hook" to trigger a 
> > general update cycle of all existing class instances upon the creation 
> > of a new class instance at the interactive prompt
> 
> class Member:
> 	members = []
> 	def __init__(self):
> 		for m in Member.members:
> 			m.notify(self)
> 		Member.members.append(self)
> 	def notify(self,other):
> 		print self,"a new member:",other

Though you will probably want to use weak references in
Member.members, unless you intend that all instances of the class
live as long as the class does.

-- 
Steven Taschuk                             staschuk at telusplanet.net
"I may be wrong but I'm positive."  -- _Friday_, Robert A. Heinlein





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